1.\" Copyright (c) 1983, 1990, 1992, 1993 2.\" The Regents of the University of California. All rights reserved. 3.\" 4.\" Redistribution and use in source and binary forms, with or without 5.\" modification, are permitted provided that the following conditions 6.\" are met: 7.\" 1. Redistributions of source code must retain the above copyright 8.\" notice, this list of conditions and the following disclaimer. 9.\" 2. Redistributions in binary form must reproduce the above copyright 10.\" notice, this list of conditions and the following disclaimer in the 11.\" documentation and/or other materials provided with the distribution. 12.\" 4. Neither the name of the University nor the names of its contributors 13.\" may be used to endorse or promote products derived from this software 14.\" without specific prior written permission. 15.\" 16.\" THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 17.\" ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 18.\" IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 19.\" ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 20.\" FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 21.\" DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 22.\" OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 23.\" HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 24.\" LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 25.\" OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 26.\" SUCH DAMAGE. 27.\" 28.\" @(#)netstat.1 8.8 (Berkeley) 4/18/94 29.\" $FreeBSD$ 30.\" 31.Dd October 15, 2013 32.Dt NETSTAT 1 33.Os 34.Sh NAME 35.Nm netstat 36.Nd show network status 37.Sh DESCRIPTION 38The 39.Nm 40command symbolically displays the contents of various network-related 41data structures. 42There are a number of output formats, 43depending on the options for the information presented. 44.Bl -tag -width indent 45.It Xo 46.Bk -words 47.Nm 48.Op Fl AaLnSTWx 49.Op Fl f Ar protocol_family | Fl p Ar protocol 50.Op Fl M Ar core 51.Op Fl N Ar system 52.Ek 53.Xc 54Display a list of active sockets 55(protocol control blocks) 56for each network protocol, 57for a particular 58.Ar protocol_family , 59or for a single 60.Ar protocol . 61If 62.Fl A 63is also present, 64show the address of a protocol control block (PCB) 65associated with a socket; used for debugging. 66If 67.Fl a 68is also present, 69show the state of all sockets; 70normally sockets used by server processes are not shown. 71If 72.Fl L 73is also present, 74show the size of the various listen queues. 75The first count shows the number of unaccepted connections, 76the second count shows the amount of unaccepted incomplete connections, 77and the third count is the maximum number of queued connections. 78If 79.Fl S 80is also present, 81show network addresses as numbers (as with 82.Fl n ) 83but show ports symbolically. 84If 85.Fl x 86is present, display socket buffer and tcp timer statistics for each internet socket. 87When 88.Fl T 89is present, display information from the TCP control block, including 90retransmits, out-of-order packets received, and zero-sized windows advertised. 91.It Xo 92.Bk -words 93.Nm 94.Fl i | I Ar interface 95.Op Fl abdhnW 96.Op Fl f Ar address_family 97.Ek 98.Xc 99Show the state of all network interfaces or a single 100.Ar interface 101which have been auto-configured 102(interfaces statically configured into a system, but not 103located at boot time are not shown). 104An asterisk 105.Pq Dq Li * 106after an interface name indicates that the interface is 107.Dq down . 108If 109.Fl a 110is also present, multicast addresses currently in use are shown 111for each Ethernet interface and for each IP interface address. 112Multicast addresses are shown on separate lines following the interface 113address with which they are associated. 114If 115.Fl b 116is also present, show the number of bytes in and out. 117If 118.Fl d 119is also present, show the number of dropped packets. 120If 121.Fl h 122is also present, print all counters in human readable form. 123If 124.Fl W 125is also present, print interface names using a wider field size. 126.It Xo 127.Bk -words 128.Nm 129.Fl w Ar wait 130.Op Fl I Ar interface 131.Op Fl d 132.Op Fl M Ar core 133.Op Fl N Ar system 134.Op Fl q Ar howmany 135.Ek 136.Xc 137At intervals of 138.Ar wait 139seconds, 140display the information regarding packet 141traffic on all configured network interfaces 142or a single 143.Ar interface . 144If 145.Fl q 146is also present, exit after 147.Ar howmany 148outputs. 149If 150.Fl d 151is also present, show the number of dropped packets. 152.It Xo 153.Bk -words 154.Nm 155.Fl s Op Fl s 156.Op Fl z 157.Op Fl f Ar protocol_family | Fl p Ar protocol 158.Op Fl M Ar core 159.Op Fl N Ar system 160.Ek 161.Xc 162Display system-wide statistics for each network protocol, 163for a particular 164.Ar protocol_family , 165or for a single 166.Ar protocol . 167If 168.Fl s 169is repeated, counters with a value of zero are suppressed. 170If 171.Fl z 172is also present, reset statistic counters after displaying them. 173.It Xo 174.Bk -words 175.Nm 176.Fl i | I Ar interface Fl s 177.Op Fl f Ar protocol_family | Fl p Ar protocol 178.Op Fl M Ar core 179.Op Fl N Ar system 180.Ek 181.Xc 182Display per-interface statistics for each network protocol, 183for a particular 184.Ar protocol_family , 185or for a single 186.Ar protocol . 187.It Xo 188.Bk -words 189.Nm 190.Fl m 191.Op Fl M Ar core 192.Op Fl N Ar system 193.Ek 194.Xc 195Show statistics recorded by the memory management routines 196.Pq Xr mbuf 9 . 197The network manages a private pool of memory buffers. 198.It Xo 199.Bk -words 200.Nm 201.Fl B 202.Op Fl z 203.Op Fl I Ar interface 204.Ek 205.Xc 206Show statistics about 207.Xr bpf 4 208peers. 209This includes information like 210how many packets have been matched, dropped and received by the 211bpf device, also information about current buffer sizes and device 212states. 213.It Xo 214.Bk -words 215.Nm 216.Fl r 217.Op Fl AanW 218.Op Fl F Ar fibnum 219.Op Fl f Ar address_family 220.Op Fl M Ar core 221.Op Fl N Ar system 222.Ek 223.Xc 224Display the contents of routing tables. 225When 226.Fl f 227is specified, a routing table for a particular 228.Ar address_family 229is displayed. 230When 231.Fl F 232is specified, a routing table with the number 233.Ar fibnum 234is displayed. 235If the specified 236.Ar fibnum 237is -1 or 238.Fl F 239is not specified, 240the default routing table is displayed. 241If 242.Fl A 243is also present, 244show the contents of the internal Patricia tree 245structures; used for debugging. 246If 247.Fl a 248is also present, 249show protocol-cloned routes 250(routes generated by an 251.Dv RTF_PRCLONING 252parent route); 253normally these routes are not shown. 254When 255.Fl W 256is also present, 257show the path MTU 258for each route, 259and print interface 260names with a wider 261field size. 262.It Xo 263.Bk -words 264.Nm 265.Fl rs 266.Op Fl s 267.Op Fl M Ar core 268.Op Fl N Ar system 269.Ek 270.Xc 271Display routing statistics. 272If 273.Fl s 274is repeated, counters with a value of zero are suppressed. 275.It Xo 276.Bk -words 277.Nm 278.Fl g 279.Op Fl W 280.Op Fl f Ar address_family 281.Op Fl M Ar core 282.Op Fl N Ar system 283.Ek 284.Xc 285Display the contents of the multicast virtual interface tables, 286and multicast forwarding caches. 287Entries in these tables will appear only when the kernel is 288actively forwarding multicast sessions. 289This option is applicable only to the 290.Cm inet 291and 292.Cm inet6 293address families. 294.It Xo 295.Bk -words 296.Nm 297.Fl gs 298.Op Fl s 299.Op Fl f Ar address_family 300.Op Fl M Ar core 301.Op Fl N Ar system 302.Ek 303.Xc 304Show multicast routing statistics. 305If 306.Fl s 307is repeated, counters with a value of zero are suppressed. 308.It Xo 309.Bk -words 310.Nm 311.Fl Q 312.Ek 313.Xc 314Show 315.Xr netisr 9 316statistics. 317The flags field shows available ISR handlers: 318.Bl -column ".Li W" ".Dv NETISR_SNP_FLAGS_DRAINEDCPU" 319.It Li C Ta Dv NETISR_SNP_FLAGS_M2CPUID Ta "Able to map mbuf to cpu id" 320.It Li D Ta Dv NETISR_SNP_FLAGS_DRAINEDCPU Ta "Has queue drain handler" 321.It Li F Ta Dv NETISR_SNP_FLAGS_M2FLOW Ta "Able to map mbuf to flow id" 322.El 323.El 324.Pp 325Some options have the general meaning: 326.Bl -tag -width flag 327.It Fl f Ar address_family , Fl p Ar protocol 328Limit display to those records 329of the specified 330.Ar address_family 331or a single 332.Ar protocol . 333The following address families and protocols are recognized: 334.Pp 335.Bl -tag -width ".Cm netgraph , ng Pq Dv AF_NETGRAPH" -compact 336.It Em Family 337.Em Protocols 338.It Cm inet Pq Dv AF_INET 339.Cm divert , icmp , igmp , ip , ipsec , pim, sctp , tcp , udp 340.It Cm inet6 Pq Dv AF_INET6 341.Cm icmp6 , ip6 , ipsec6 , rip6 , tcp , udp 342.It Cm pfkey Pq Dv PF_KEY 343.Cm pfkey 344.It Cm atalk Pq Dv AF_APPLETALK 345.Cm ddp 346.It Cm netgraph , ng Pq Dv AF_NETGRAPH 347.Cm ctrl , data 348.It Cm ipx Pq Dv AF_IPX 349.Cm ipx , spx 350.\".It Cm ns Pq Dv AF_NS 351.\".Cm idp , ns_err , spp 352.\".It Cm iso Pq Dv AF_ISO 353.\".Cm clnp , cltp , esis , tp 354.It Cm unix Pq Dv AF_UNIX 355.It Cm link Pq Dv AF_LINK 356.El 357.Pp 358The program will complain if 359.Ar protocol 360is unknown or if there is no statistics routine for it. 361.It Fl M 362Extract values associated with the name list from the specified core 363instead of the default 364.Pa /dev/kmem . 365.It Fl N 366Extract the name list from the specified system instead of the default, 367which is the kernel image the system has booted from. 368.It Fl n 369Show network addresses and ports as numbers. 370Normally 371.Nm 372attempts to resolve addresses and ports, 373and display them symbolically. 374.It Fl W 375In certain displays, avoid truncating addresses even if this causes 376some fields to overflow. 377.El 378.Pp 379The default display, for active sockets, shows the local 380and remote addresses, send and receive queue sizes (in bytes), protocol, 381and the internal state of the protocol. 382Address formats are of the form 383.Dq host.port 384or 385.Dq network.port 386if a socket's address specifies a network but no specific host address. 387When known, the host and network addresses are displayed symbolically 388according to the databases 389.Xr hosts 5 390and 391.Xr networks 5 , 392respectively. 393If a symbolic name for an address is unknown, or if 394the 395.Fl n 396option is specified, the address is printed numerically, according 397to the address family. 398For more information regarding 399the Internet IPv4 400.Dq dot format , 401refer to 402.Xr inet 3 . 403Unspecified, 404or 405.Dq wildcard , 406addresses and ports appear as 407.Dq Li * . 408.Pp 409The interface display provides a table of cumulative 410statistics regarding packets transferred, errors, and collisions. 411The network addresses of the interface 412and the maximum transmission unit 413.Pq Dq mtu 414are also displayed. 415.Pp 416The routing table display indicates the available routes and their status. 417Each route consists of a destination host or network, and a gateway to use 418in forwarding packets. 419The flags field shows a collection of information about the route stored 420as binary choices. 421The individual flags are discussed in more detail in the 422.Xr route 8 423and 424.Xr route 4 425manual pages. 426The mapping between letters and flags is: 427.Bl -column ".Li W" ".Dv RTF_WASCLONED" 428.It Li 1 Ta Dv RTF_PROTO1 Ta "Protocol specific routing flag #1" 429.It Li 2 Ta Dv RTF_PROTO2 Ta "Protocol specific routing flag #2" 430.It Li 3 Ta Dv RTF_PROTO3 Ta "Protocol specific routing flag #3" 431.It Li B Ta Dv RTF_BLACKHOLE Ta "Just discard pkts (during updates)" 432.It Li b Ta Dv RTF_BROADCAST Ta "The route represents a broadcast address" 433.It Li C Ta Dv RTF_CLONING Ta "Generate new routes on use" 434.It Li c Ta Dv RTF_PRCLONING Ta "Protocol-specified generate new routes on use" 435.It Li D Ta Dv RTF_DYNAMIC Ta "Created dynamically (by redirect)" 436.It Li G Ta Dv RTF_GATEWAY Ta "Destination requires forwarding by intermediary" 437.It Li H Ta Dv RTF_HOST Ta "Host entry (net otherwise)" 438.It Li L Ta Dv RTF_LLINFO Ta "Valid protocol to link address translation" 439.It Li M Ta Dv RTF_MODIFIED Ta "Modified dynamically (by redirect)" 440.It Li R Ta Dv RTF_REJECT Ta "Host or net unreachable" 441.It Li S Ta Dv RTF_STATIC Ta "Manually added" 442.It Li U Ta Dv RTF_UP Ta "Route usable" 443.It Li W Ta Dv RTF_WASCLONED Ta "Route was generated as a result of cloning" 444.It Li X Ta Dv RTF_XRESOLVE Ta "External daemon translates proto to link address" 445.El 446.Pp 447Direct routes are created for each 448interface attached to the local host; 449the gateway field for such entries shows the address of the outgoing interface. 450The refcnt field gives the 451current number of active uses of the route. 452Connection oriented 453protocols normally hold on to a single route for the duration of 454a connection while connectionless protocols obtain a route while sending 455to the same destination. 456The use field provides a count of the number of packets 457sent using that route. 458The interface entry indicates the network interface utilized for the route. 459.Pp 460When 461.Nm 462is invoked with the 463.Fl w 464option and a 465.Ar wait 466interval argument, it displays a running count of statistics related to 467network interfaces. 468An obsolescent version of this option used a numeric parameter 469with no option, and is currently supported for backward compatibility. 470By default, this display summarizes information for all interfaces. 471Information for a specific interface may be displayed with the 472.Fl I 473option. 474.Pp 475The 476.Xr bpf 4 477flags displayed when 478.Nm 479is invoked with the 480.Fl B 481option represent the underlying parameters of the bpf peer. 482Each flag is 483represented as a single lower case letter. 484The mapping between the letters and flags in order of appearance are: 485.Bl -column ".Li i" 486.It Li p Ta Set if listening promiscuously 487.It Li i Ta Dv BIOCIMMEDIATE No has been set on the device 488.It Li f Ta Dv BIOCGHDRCMPLT No status: source link addresses are being 489filled automatically 490.It Li s Ta Dv BIOCGSEESENT No status: see packets originating locally and 491remotely on the interface. 492.It Li a Ta Packet reception generates a signal 493.It Li l Ta Dv BIOCLOCK No status: descriptor has been locked 494.El 495.Pp 496For more information about these flags, please refer to 497.Xr bpf 4 . 498.Pp 499The 500.Fl x 501flag causes 502.Nm 503to output all the information recorded about data 504stored in the socket buffers. 505The fields are: 506.Bl -column ".Li R-MBUF" 507.It Li R-MBUF Ta Number of mbufs in the receive queue. 508.It Li S-MBUF Ta Number of mbufs in the send queue. 509.It Li R-CLUS Ta Number of clusters, of any type, in the receive 510queue. 511.It Li S-CLUS Ta Number of clusters, of any type, in the send queue. 512.It Li R-HIWA Ta Receive buffer high water mark, in bytes. 513.It Li S-HIWA Ta Send buffer high water mark, in bytes. 514.It Li R-LOWA Ta Receive buffer low water mark, in bytes. 515.It Li S-LOWA Ta Send buffer low water mark, in bytes. 516.It Li R-BCNT Ta Receive buffer byte count. 517.It Li S-BCNT Ta Send buffer byte count. 518.It Li R-BMAX Ta Maximum bytes that can be used in the receive buffer. 519.It Li S-BMAX Ta Maximum bytes that can be used in the send buffer. 520.El 521.Sh SEE ALSO 522.Xr fstat 1 , 523.Xr nfsstat 1 , 524.Xr procstat 1 , 525.Xr ps 1 , 526.Xr sockstat 1 , 527.Xr bpf 4 , 528.Xr inet 4 , 529.Xr route 4 , 530.Xr unix 4 , 531.Xr hosts 5 , 532.Xr networks 5 , 533.Xr protocols 5 , 534.Xr services 5 , 535.Xr iostat 8 , 536.Xr route 8 , 537.Xr trpt 8 , 538.Xr vmstat 8 , 539.Xr mbuf 9 540.Sh HISTORY 541The 542.Nm 543command appeared in 544.Bx 4.2 . 545.Pp 546IPv6 support was added by WIDE/KAME project. 547.Sh BUGS 548The notion of errors is ill-defined. 549